Epidurals with fentanyl not linked to lower odds of breastfeeding

(Reuters Health) - Women who get epidural pain relief that includes the opioid fentanyl are no less likely to breastfeed their babies than mothers who get epidurals without this drug, a small study suggests.

Epidurals often contain a combination of fentanyl and a local anesthetic such as bupivacaine because using the combination allows doctors to give women lower doses of each drug. Some previous research suggests that fentanyl, particularly in higher doses, may make it harder for newborns to breastfeed because it crosses from mothers to babies through the placenta and can cause sleepiness and feeding difficulties for the infants.

For the current study, researchers tested different epidural solutions in 345 pregnant women who had successfully breastfed at least one baby before. The participants were randomly assigned to receive bupivacaine alone or bupivacaine combined with either 1 or 2 micrograms per milliliter of fentanyl.

After six weeks, 97 percent of babies in the bupivacaine-only group were breastfeeding, as were 98 percent of infants with the lower dose of fentanyl and 94 percent of newborns with the higher fentanyl dose.

These differences were too small to rule out the possibility that they were due to chance, researchers report in Anesthesiology.

“We studied women that had previously breastfed and were highly motivated to breastfeed with their current infant,” said study co-author Robert McCarthy, an anesthesiology researcher at Northwestern University Feinberg School of Medicine in Chicago.

“Therefore it is not surprising that the success rate is high,” McCarthy said by email.

It’s possible the results would be different for first-time mothers without any previous experience breastfeeding, or with higher doses of fentanyl, McCarthy added. The study was also done at a so-called “baby friendly” hospital with extra services to support breastfeeding.

“This is a group of mothers that was headed for success,” said Dr. Lydia Furman a researcher at Case Western Reserve University and University Hospitals Rainbow Babies and Children’s Hospital in Cleveland, Ohio.

“Whether this is clearly generalizable to all mothers is not completely clear to me though the results are encouraging in that with good support there is no reason to avoid fentanyl among those intending to breastfeed,” Furman, who wasn’t involved in the study, said by email.

Pediatricians recommend that mothers exclusively breastfeed infants until they’re at least 6 months of age because it can reduce babies’ risk of sudden infant death syndrome (SIDS) as well as ear and respiratory infections, allergies, childhood obesity and diabetes.

Mothers can benefit too, with longer periods of breastfeeding linked to lower risks of depression, bone deterioration and certain cancers.

Many women still choose not to breastfeed or stop nursing their babies much sooner, often due to time constraints, returning to work, or being unable to afford breast pumps and other equipment needed to express milk.

The majority of the women in the current study had previously nursed a baby for at least six months, and less than 10 percent of them had stopped nursing before three months.

With a larger group of women, it’s possible that the differences in breastfeeding success based on fentanyl doses in the epidurals might have been big enough to be statistically and clinically meaningful, said Yukiko Washio, a researcher at the University of Delaware in Newark who wasn’t involved in the study.

“As a scientist, it seems that not enough evidence shows that epidural fentanyl is adversely impacting the initiation and duration of breastfeeding among women who are highly motivated to breastfeed with previous breastfeeding experiences at this point,” Washio said by email.

“However, replications of this type of study with more power in a similar cohort and with different cohorts of women are required to confirm that for longer-term breastfeeding outcomes to make any definite recommendation as the standard guideline for patients,” Washio added.